Question

Solve the equation using quadrant formula. 9x^2 − 3x − 2 = 0

Answer 1

-b/a = x1+x2 and c/a = x1*x2
3/9 = x1+x2
-2/9 = x1*x2

Answer 2

Presumably you mean the quadratic formula. For an equation of the form:
$$ax^2 + bx + c = 0,$$
The quadratic formula is:
$$x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}$$

Your equation is:
$$9x^2 - 3x -2 = 0.$$

In other words, a=9, b=-3, c = -2. Plug and play!